Cant get my New DDR4 RAM to work

new pc? what is the full system spec? include make and model of the psu

Hi Ompalompa!
So to be clear, your PC does work with one stick, correct? Then if you add the "faulty" one it doesn't.

This happened to me with a brand new build. One of my ram sticks (also a Corsair Vengeance btw) wasn't working properly so I had it tested and it turned out it was a manufacturing error.

If yours is brand new, you could take it back to the store where you bought it and explain the situation (with your receipt, if you are still under the store warranty policies). Otherwise, Corsair has a one-year warranty as well. I had to send them my faulty stick and they replaced it. No problem after that. You can find the info on returning a product to Corsair on their web page.

I hope this helps.

Cheers,
J

First off, make sure there is not a newer bios image available for your motherboard on the Gigabyte product page.

Second, that is normal. The Gigabyte Z170 boards will not allow changes to memory voltage in increments less than .020v, so you can set the DRAM voltage at 1.34, 1.36, 1.38, etc., but not 1.35, 1.345, etc., like you can on ASUS and ASRock, perhaps MSI as well. Those boards, and even more recent chipsets by those companies as well, allow for increments of .005v when making changes to DRAM voltage.

Only when the XMP profile is set will it allow 1.35v, and it will do that automatically. There is nothing wrong with setting the DRAM voltage to 1.36v if the system is having stability issues with the DRAM at the 1.35v XMP profile value.

If you wish to make changes to the memory speed, you don't change the frequency, that will be grayed out and not adjustable. You make changes to the multiplier. For example, a multi of 30 gives you 3000mhz. A multi of 32 gives you 3200mhz. You can set the memory to Profile 1 of the XMP configuration and STILL make changes to speed, voltage and timings, but if you wish to change timings you'll want to change the timing mode to manual then go into the timings sub-setting and make your changes. Also, I've not had any success running a Command rate of 1 on the Z170x-Gaming 5 or 7, using both G.Skill and Corsair sticks (Trident-Z and Dominator) so you may wish to try a 2T command rate unless your sticks specifically say that a command rate of 1 should be used. I know that 1T is faster, but I've had trouble getting memory to run at that on those Gigabyte boards and on a Hero VIII with an overclocked 6700k.

The first thing you should do, is create bootable Memtest86 (Passmark) USB media and then boot to Memtest. Test those sticks at the DEFAULT configuration of 2133mhz with NO XMP enabled to make sure there is nothing physically wrong with them before trying to configure them manually or setting the XMP profile. If they pass two full passes of Memtest86, then you can enable the XMP profile (Usually Profile 1) and test in Memtest again. If they pass four passes, great. If not, increase the DRAM voltage to 1.36v and try again.

Often, it is necessary to apply at least a small overclock to the CPU to get DRAM to run at higher speeds. On Skylake, I've found that anything over 2666mhz requires at least a full time 4.2Ghz about 50% of the time to stabilize the memory at anything over 2800mhz.

AND, if you are going to overclock the CPU, you want to do that FIRST, before changing the memory from the default configuration at all.

Try only one stick, in the A2 slot, set the XMP profile in the bios, change the DRAM voltage to 1.36v. Save settings, exit, power off, install the other module in the B2 slot, power on, see if works now.

Before doing that though, with just one module installed, I'd update the BIOS. Here's how.

Go to the product page for your motherboard model. Make sure it is the page for the same REVISION number, as the K3 Gaming might have more than one revision, for example, Gaming K3 v1.0, v2.0, etc. Download the latest bios image. Unzip the downloaded file and put the contents on a USB thumb drive.

Then, as follows:

https://www.youtube.com/watch?v=ze4Dg11W3hU